doc: Added suit and smp doc

Added suit and smp doc.

Signed-off-by: Francesco Domenico Servidio <[email protected]>

Author: FrancescoSer

doc/nrf/app_dev/device_guides/working_with_nrf/nrf54h/ug_nrf54h20_suit_dfu.rst

@@ -27,6 +27,7 @@ For a list of available SUIT samples, see the :ref:`suit_samples` page.
    ug_nrf54h20_suit_device_config.rst
    ug_nrf54h20_suit_customize_qsg.rst
    ug_nrf54h20_suit_customize_dfu.rst
+   ug_nrf54h20_suit_smp.rst
    ug_nrf54h20_suit_fetch
    ug_nrf54h20_suit_push
    ug_nrf54h20_suit_external_memory